Best Mods for E46 M3 in 2019 – Show and Track

E46 M3 Track Section:

This section will be a little different, and most of it will not apply to only the E46 M3. The majority of the advice given in this portion of the article can apply to any car you will be taking to the track. Please keep in mind however that any part recommendations are selected solely for the E46 M3.

The first thing you have to understand about tracking is that it’s not really a race against anyone but yourself. Sure if you’ve got a buddy with an E46 M3 you may compete for best lap time but even between the same model of car there can be variances you may not account for, the only thing you can be 100% sure of is what your own car can do from day to day. This is why your mission is initially going to be just learning the track you’re driving. Once you’ve done that, drive it hard a few times and you’ll naturally produce a fastest lap time. Congratulations, you have now set a personal best. Now your goal is simple, try to beat it. The nice thing about that is you can literally spend zero money on mods (but please for the love of God perform all the proper maintenance) and have yourself a ton of fun on the track. You set your own goals. Therefore this isn’t a guide on how to build your track car per se, it is more of a “what to change to tackle certain situations” so you can break through that plateau you’ve hit or fix a weird behavior you’ve discovered in your car.

Handling Part 1:

You, The Driver:

First and foremost let’s discuss you as a driver. You are hands down the most important part of your track car. You can dump thousands of dollars into your car but none of it is going to make you a better driver or inherently improve your lap times, that comes with time after a lot of practice and a conscious desire to improve. You know the saying “Practice makes perfect”? Well forget that saying, it’s stupid and wrong. Some have rephrased it into “Perfect practice makes perfect”, but that doesn’t quite work either because how are you to know what perfect practice is without first discovering your imperfections? There’s no simple way of putting it, to become proficient you have to have a strong desire to improve, and you have to know how to recognize your own flaws in order to remedy them.

Have you ever met someone who thinks they’re doing something right just because they’ve been doing it for a long time? We’ve probably all met one of those people either socially or professionally. Don’t be that person, a desire to improve and a willingness to adapt are fundamental in discovering your own flaws and you should never lose that desire. Before you start modding consider some driving lessons, or if you feel that is not the best way for you to learn at least run a few sessions with your car as it is. In doing so you’ll get a good sense of your own car control abilities (given that you have a certain level of self awareness) and a better understanding of your own car’s shortcomings. Then you can start switching out parts and seeing how they affect your times.

Tires:

One of the first things you’ll want to look into upgrading is your tires. Your tires are literally your only physical connection to the road, so it makes sense that they would have the biggest impact on your performance. In addition to affecting your car’s road-holding capabilities tires also affect braking and acceleration. If you’re losing traction in turns or your ABS is kicking in super easily you should check your tires. They are either a crappy compound or they’re balding. Either way, it’s time for a replacement if you’re getting serious about tracking.

Tires are a wear item, so if you buy a set of tires it’s not like you’re stuck with them forever, don’t be afraid to try out something cheaper before moving on to the expensive options.

Please be aware that tires generally need to be heated up steadily to avoid hotspots and promote even wear. You don’t have to go at a snail’s pace initially but don’t go full throttle right at the start. Take a lap or two at a calmer pace to get heat in the tires and then you can go full beans. Some tires warm up quicker than others but we’ll make note of that individually.

-Tire Pressure:

Tire pressures vary from person to person for a given car they usually stay within a range of 2 or 3 psi. For the E46 M3 most people run between 32-36 psi hot. Now be careful, this doesn’t mean you’re going to just inflate your tires to 34/35 psi and leave them. Track tire pressures are measure when the tire has reached operating temperature (air will expand when it gets hot), so you’ll want to set them to around 30 psi to start with then get them warmed up. Once you’ve run your laps for your 20-25 minute session go ahead and check your tire pressures and make sure they’re not getting too high.

We highly recommend getting yourself a tire pyrometer of some sort. An infrared temperature gun, while less accurate, is cheaper than one with a probe so if your budget is tight it is a good option. However a probe will give you internal temp of the rubber so you get the most accurate reading. The reason why we measure tire temperatures is to check that your tires are contacting the track evenly. If the temperature at the center of the tire is higher than the sides then your pressure is too high. If it is too high at both edges then your pressure are too low. If it is too high at the inside or outside edge then your negative camber settings are too high or low respectively.

The reason a probe is preferable for reading temperatures is because it reads internal temperatures instead of surface temps. As you drive back to the pits your tires are in contact with colder pavement which will slowly absorb heat from your tires. Because you will be running a fair amount of camber your tires will not be in full contact with the pavement all the way back to the pits, meaning the surface on the inner edge of your tire will have cooled off more than the outside edge. Just keep that in mind if you are using a surface infrared temperature gun.

-Max Performance Summer:

If you’re just getting into tracking your car you probably don’t want to be immediately spending over $1000 on a set of tires you don’t really know the full benefits of yet. A set of Max Performance Summer tires will give you a good amount of performance but will still have a feeling of familiarity in terms of treadwear and pricing.

The Nitto NT05 is a tire that has an impressive amount of grip for a strictly street oriented tire. They are great for if you’re just getting into tracking and you’re curious what a stickier tire can do for you. They won’t last very long at all if you’re used to normal street tires with 300+ treadwear, but that’s something you’ll have to get used to if you’re going to be tracking your car. The stickier the tires, the faster they’ll wear out.

-Extreme Performance Summer:

Extreme Performance Summer tires are a step up from Max Performance tires and are, for most, the ideal blend of performance and longevity. You’ll get superb lateral grip while maintaining decent wet performance and enough treadwear to get you through at least a few track days. We’ve listed a couple of the favorites from the enthusiast community below, but there are so many options out there you should not limit yourself to only these choices. A big part of tire choice is personal preference, you won’t perform as well with a tire you don’t like the feel of.

The Ventus R-S4 is a solid performer in this category. Its dry performance is extremely good but what really makes it stand out is its longevity. Users report superb treadwear, with the R-S4 lasting a significant amount longer than some of the higher performing tires in this category. Water should also be avoided if possible with this tire as its tread pattern makes it a little prone to aquaplaning so maybe keep your stock wheels and tires around for use when driving on normal roads.

Like the Hankooks these Azenis RT615K+ are a very solid performer with good tread life and excellent grip. We’d say try either these or the Hankooks first, then switch and see which you like better. They are priced so very similarly so there’s really no reason not to give each a fair try, and driving on different types of tires can only do good things to the development of your driver skills.

The RE-71R is a standout in this category due to its impressive levels of grip but comparably low tread life. It is designed and manufactured with the intent of being used in autocross driving (short sprints) rather than full track days so they heat up faster than most but can overheat faster as well. They won’t be completely destroyed after a normal track session, but if you’re driving at your absolute limit for the whole 20-25 minutes you are going to be within the upper end of their heat tolerance and will be losing grip steadily near the end.

The BFG Rival S is a solid tire. Excellent grip and very good tread life. We just have trouble recommending them right off the bat because they are also significantly more expensive than all the other options listed here. It’s a case of “you get what you pay for” of course, but the extra performance will be marginal while the initial money out of pocket will be noticeable. We suggest trying some other tires first and if you’re itching for something new and different give these a go.

DOT Competition Tires:

These exist, and will give you insane levels of dry grip, but we hesitate to recommend any because they are a heavy investment and behave a little differently than normal tires. A normal tire will give you a fair amount of warning before losing traction. A racing tire on the other hand, while having much higher limits, also has a much smaller grace period before letting go completely. However, if you’re at the point where you’re buying racing tires you hopefully don’t need advice from us and know the benefits/risks of them.

Wheels:

For a track car aftermarket wheels are not 100% essential, but they will allow you certain benefits such as fitment of wider tires and/or reducing your unsprung weight. If you’re running stock wheels then you’re dealing with either a staggered set of 18×8.0/18×9.0 wheels or 19×8.0/19×9.5 wheels. Both of these sets have their drawbacks but either will work for you initially as you get accustomed to the car. However, once you are feeling a little more confident you’ll definitely want to consider upgrading. The factory wheels are cast (see page 2 for details on cast wheel construction) so not only are they not made to withstand the punishment of repeated track days, they are also quite heavy which hampers performance. If you’re looking to replace them you have a few options. If you are completely attached to the factory handling characteristics you can get a staggered set, or if you want more of a neutral feel you can go with a square setup (all four corners the same size wheel). This is a very popular option with E46 M3 track enthusiasts and will be highly recommended by most.

-Rotating Mass and Unsprung Weight:

Reduction in rotating mass is the main benefit of equipping your vehicle with lightweight wheels. Your engine produces a set amount of power that is transmitted through the drivetrain to the wheels to make the car accelerate. It is important to reduce rotating mass because the more of it you have then the more engine torque is wasted on spinning the wheel and tire, meaning less is available for the job of propelling the vehicle forward. For anyone who doesn’t know how torque works: torque is simply a force at a distance, which is why it is measured in foot-pounds. Imagine you had a wrench with a 1 foot handle and you are turning a bolt with it. If you exert 1 pound of pressure at the very end of that wrench, the bolt is being turned with 1 ft-lb of torque.

Now think about the mass of a wheel and where most of the weight is. The face of the wheel is relatively void of material, but the barrel is solid metal, meaning most of the mass is a decent distance from the center-point. When a tire is installed then you have even more weight at the outside edge of the wheel. This means that to turn the wheel you need more torque to spin that whole mass. Reducing the weight of the wheel therefore frees up engine power that can then more freely accelerate the car itself. Furthermore, this affects your brakes’ effectiveness at stopping your car as well. Higher rotating mass means that while the wheel is spinning it has more inertia, which requires more force from your brakes to reduce its speed. Reducing the rotating mass means your brakes are less burdened with the job of stopping the wheels themselves and can work harder against your vehicle’s inertia.

In addition to reduction in rotating mass, lighter wheels reduce your vehicle’s unsprung mass. Unsprung mass is the mass of your vehicle that moves with the wheels when you hit a bump. The more unsprung mass you have, the more inertia that has to be handled by the suspension. This directly affects your vehicle’s compliance with road irregularities. If your wheels have a lot of inertia they will not be able to keep up with every bump and dip you encounter so your vehicle will feel “floaty”. A lightweight wheel reacts more quickly and therefore helps you keep a consistent contact patch with the road.

-Rotating Mass Exercise:

If you would like a real world test you can perform on your own vehicle, we have an easy process that can be used in your own garage.

Jack your vehicle up and place the front of the car on jack stands.

Your front wheels should be hanging in the air.

At this point we recommend putting on some thick gloves because you’re going to be touching your tires and they are usually not very clean.

Gripping the passenger side tire with both hands, spin the wheel in a clockwise direction as hard as you can.

Make note of the effort it took to spin it.

Now try to bring the tire to a stop with your gloved hands

Once you get the wheel stopped, make note of the effort needed to stop the wheel spinning.

Now spin the wheel again, this time gripping as close to the center of the wheel as possible, you should notice that the effort required to spin the wheel increases drastically.

Do not try to stop the wheel in the same manner, that’s a good way of injuring yourself by catching a finger in the spokes of your wheel.

Now we will go over why you did all this. First, spinning the wheel from the tire gives you an idea of the effort needed to get a single wheel going. Next, stopping the wheel gives you an idea of the amount of force required to bring just the wheel to a stop. Finally, spinning the wheel from the inner edge of the spokes should give you an idea of how much more effort is required to accelerate a wheel when force is applied closer to its center. It’s too dangerous to try, but if you were to try to stop the wheel spinning by grabbing the inner edge of the spokes you would see that this also takes a great deal more effort. If you have a lighter wheel available or a wheel without a tire, repeat the test and you’ll see that it takes noticeably less effort to manipulate the speed of the lighter wheel.

-Sizing:

There are a lot of wheels that can fit the M3, we’re not going to cover all of them, we’re just going to cover the upper end of sizes. For example, if we say a 17×9.5 square setup with an offset of ET35 using 255/40R17 tires will fit (with the use of a spacer in this case) with -2.5 degrees of camber in the front, it can be deduced that a 17×9 of the same offset will also fit. The smaller size may not need the same spacer for clearance, but it also will not fill out the fender as much so you are not fully utilizing the space available to you.

-Square Setups

A square setup is very beneficial to the E46 M3’s handling characteristics because of the car’s inherent 50-50 weight distribution. For anyone who is unaware, a 50-50 weight distribution means exactly half of the car’s weight is supported by the front axle and half is supported by the rear axle (it is almost never exactly 50% on each axle but it is within a small margin of error). The benefit of this weight distribution when combined with a square tire setup is that you get very balanced handling characteristics. There is also the added convenience of being able to rotate your tires from front to back, so you get the most out of them as opposed to a staggered setup where they’re stuck where they are. You also have a choice between 17″ and 18″ diameters (19″ would be a bit too large and would also make for more expensive tire purchases). 17″ will be a little bit lighter and the taller sidewalls will give a much more compliant ride. 18″ will be more responsive because of the shorter sidewall, and a bit more expensive. Furthermore, in the future as vehicles move towards bigger and bigger wheel sizes you’ll find 18″ tires more readily available, so that’s also something to consider.

Note from the author: Take it from someone who has 16″ wheels on his own vehicle, it is a huge pain to find a good selection of tires in smaller sizes, especially for a staggered set of wheels.

This is a more conservative fitment typically used with a 255/40-17 tire which will fit without any aggressive camber settings. A 5mm spacer may be required depending on what aftermarket suspension you choose (see our track suspension subsection for more details), but this spacer should not adversely affect your vehicle. If you want it a little more aggressive you can fit 275/40-17 tires but to do so you will need to have around 2.5 degrees of camber on your front wheels.

These two fitments kind of go hand in hand. They are both 18×9.5″ and take the same tire sizes, the difference is their requirements for fitment. To fit a 265/35-18 on an 18×9.5″ ET35 you only need about 2 degrees of negative camber and to fit a 275/35-18 you need about 2.5 degrees. However, like with the 17×9.5” ET35, you may need a 5mm spacer on your fronts depending on your choice of suspension. On the other hand, a 18×9.5” ET22 will fit either tire without the need for a spacer, you will just have to make sure you have camber plates that can give you up to 3 degrees of negative camber in the front for a 265/35-18 or 3.5 degrees for the 275/35-18.

18×10” ET25 – 275/35-18 or 285/30-18

A very popular fitment for E46 M3 owners is the 18×10” ET25. This is a tiny bit more aggressive than the fitments above but you really don’t need that much more negative camber to fit them, maybe half a degree front and back. You can run the same 275/35-18 as the previous two fitments, or you can go with slightly bigger 285/30-18. To fit the 285s you’ll need a little over 3.5 degrees of negative camber, and you may even need to roll your front fenders a tiny bit depending on what tire you get (widths can vary). If you have a set of the camber plates we mention later on page 8 you should be totally fine. Oh and if you want the rear to fit a little more flush you can run a small spacer back there (3-5mm).

-Staggered Setups

A staggered setup will feel the most familiar if you’ve been driving the car a long time with the stock wheel setup. This is not the recommended setup but if you are strangely attached to the stock handling behavior of the M3 then either of these setups will allow for very aggressive tire sizing while requiring no extra camber or spacers. Keep in mind that your tires will wear faster with this kind of setup because they cannot be rotated from front to back.

F: 17×9” ET30 – 245/40-17 or 255/40-17
R: 17×10” ET25 – 275/40-17

F: 18×9″ ET30 – 245/40-18 or 255/35-18
R: 18×10″ ET25 – 275/35-18

Not much explanation needed, you can fit either a 245 or 255 in the front of both fitments depending on if you want a little bit more grip up front. Otherwise it’s pretty straightforward, just install and have fun.

-Flow Formed Construction:

If you’re buying new wheels for the track, just leave cast wheels out of consideration, spend a little bit extra and go flow formed, you’ll be happy you did. Eventually you’ll want a fully forged wheel for the best in strength and lightness but you can work your way up to that. Investing in forged wheels right off the bat is going to cost you quite a bit more so unless you have deep pockets it’s not advisable.

The Sportline 8S is one you might recognize from our show wheels subsection. It’s a wheel that looks great while performing well. Its flow formed construction gives it a good deal of strength and low weight which is perfect for an affordable track wheel. Currently the only fitment that the 8S meets is the 18×9.5 ET22 so if you want one of the other more aggressive or conservative fitments you should consider one of our other wheel options.

We can’t really have a flow formed wheel subsection without bringing up the Forgestar F14 again. All the things that make it a great show wheel also make it a good pick for a track wheel. You can choose between 17″ diameter and 18″ diameter, select your desired width, and choose your ideal offsets (or leave it to Forgestar to determine proper offsets for your vehicle and chosen width/diameter). You also have a bunch of color options so you can make your track car look as fun as it feels. F14s are capable of being built in any of the fitments mentioned above so you really have a lot of options with this wheel.

-Forged Construction:

Forged wheels are what you want to aim for once you’ve decided you’re going to go pretty hardcore into tracking your car. They’re the lightest and strongest wheels you can get without selling organs (forged magnesium and carbon fiber wheels are a thing if you happen to be a Rockefeller). With a set of forged wheels you can drive with confidence knowing your wheels can deal with all the punishment you can dish out. Just be aware that all wheels, no matter the construction, will eventually fail after repeated track abuse, wheels should be inspected after every session for cracks or signs of impending failure.

While the custom nature of BC Forged does make them more suited for show cars, they are still fully forged so they can of course handle their fair share of track days. There is also the added bonus that you can go straight from the track to a show (maybe hit up a car wash on the way), or vice versa. Most designs are available in both 17″ and 18″ sizes and there are enough customization options on each wheel to satisfy even the pickiest of customer. We recommend sticking with monoblock wheels rather than multipiece due to the lighter weight and better air retention of a monoblock wheel, but if you’re really feeling multipiece wheels go for it, we’re not your mother.

This is the definitive track wheel. It’s built to put up with the punishment of repeated track days with the perfect blend of strength and lightness. The design also has the added benefit of excellent brake cooling. You’ll see these everywhere at enthusiast events, and given Volk’s excellent track record (hehe) with the community it should come as no surprise. We carry the TE37 Super Lap in the 18×9.5 ET22 or the TE37 Saga in an 18×9.5 ET20 (there will be no real notable change in fitment from the 18×9.5 ET22, it’s a difference of 2mm further outward so if anything your inner clearance will improve). The Saga is a tiny bit more expensive but is designed to fit bigger brakes than the Super Lap so if that is a concern of yours you should go for the Saga. Also note that it is possible to get a standard TE37 in an 18×10 ET25 if you look for a group buy on the E46 M3 Forums and other social hubs for M3 owners.